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IRJET-Behaviour of Cold Form Steel under Point Loading & Statically Defining its Limitation

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International Research Journal of Engineering and Technology (IRJET)
e-ISSN: 2395-0056
Volume: 06 Issue: 07 | July 2019
p-ISSN: 2395-0072
www.irjet.net
BEHAVIOUR OF COLD FORM STEEL UNDER POINT LOADING &
STATICALLY DEFINING ITS LIMITATION
Rahul S.Waghmare1, Prof. Prashant M. Kulkarni2
1Post
Graduate Student, Department of Civil Engineering, Trinity College of Engineering and Research,
Pune, India.
2Professor, Department of Civil Engineering, Trinity College of Engineering and Research, Pune.411048, India.
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Abstract - Cold-formed steel is highly ductile, sustainable, and
uninfluenced by insects, mold or decay. Different products are
manufactured from Cold Formed Steel (CFS) are used in the
different field of our on a daily basis life; in the home, the shop,
the factory, the office, the car, the petrol station. These
products have a lot of uses structural frame, building
members. This investigation presents the analytical study and
theoretical study of the behaviour of CFS sections. Analytical
study of CFS section was done by using FEM software (ANSYS)
workbench. Here Channel sections provided with different
stiffeners with lips and without lips. One of the C-sections is
provided with V stiffener and rectangular stiffener to increase
the flexural strength. The analytical results are compared with
experimental results according to IS 801:1975. The
experimental, analytical and arithmetical investigation is on
the interrelation between non-dimensional slenderness and
pure bending strength of stiffened cold-formed steel as a
construction material. Different types of stiffeners were
incorporated to evaluate the deformation on flexural
performance of C-sections it would be the predicted location
for local and distortional buckling. The Application of the
study to an extensive parametric study to investigate the
Deflection, Equivalent Stress and Equivalent strain modes of
specimens with different Stiffeners sizes. A nonlinear finite
element model was developed and established against the test
results in terms of failure buckling modes.
to hot rolled steel. In this paper detailed parametric and
comparative study of cold formed steel sections by different
codes is carried out for forecasting of flexural strength of
beams.
The performance of cold-formed steel members is
influenced by the material and sectional properties of the
section it can be improved by a variety of ways. The
behaviour of the cold-formed steel beam is generally
improved by the presence of intermediate and edge stiffener
stiffened elements or by making a closed profile. It can
increase the strength and improve its overall behaviour.
Subsequent are the proposed sections to be analyzed for the
projects. Thin sheet steel products are extensively used in
building industry, and vary from purlins to roof sheeting and
floor decking.
The modeling is done using the finite element
program of ANSYS 18.1 Workbench version is used to
analyse a finite element model which simulates the
behaviour and strength of the cold-formed steel channel
sections for various profiles along with three d/t ratio and
boundary conditions. Numerical analysis is to be carried out
for channel beam section by ANSYS-version 18.1 software.
1.1 Significance of Research
In this study the behaviour of channel section under point
load is studied for different types of combinations of stiffeners
with additional lip arrangement. Different types of stiffener
with variation in size and shape under intense point loading
are compared with its behaviour parameter as deflection,
buckling under loading and failure load capacity.
Key Words: Cold Formed Steel, FEM, C-sections
1. INTRODUCTION
All over the world, applications of thin-walled
sections have been a growing demand in all the engineering
industry due to their low self-weight, high performance of
structural systems with uniform quality, simple fabrication
process and cost-effective in both transport erection. Coldformed steel sections can be used effectively as a structural
element in cases where hot-rolled sections or others are not
efficient. The behaviour of the thin-walled section is
governed by various parameters such as cross-sectional
geometry and dimensions. The instabilities of thin-walled
flexural members are local, distortional, flexural torsional
buckling and their interaction between them. Cold formed
steel are currently used for building construction especially
non-load bearing partition, curved walls, etc due to its
flexural strength and good presence. The cold formed steel
enhances the mean yield stress by 15% to 30% as compared
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Simple C Section C Section with Lip V Stiffener without Lip
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e-ISSN: 2395-0056
Volume: 06 Issue: 07 | July 2019
p-ISSN: 2395-0072
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3.2 Modelling and Meshing
V Stiffener
with Lip
Rec. Stiffener
without Lip
Six models with defferent stiffeners such as simple channel
sections with and without lips, V stiffener with and without
lips, Rectangular section with and without lips used with
2mm thickness and length 1000mm. Both the ends are
simply supported wth hinge and roller. The finite element
programme of ANSYS 18.1 workbench is used develop finite
element models, which aimed to simulate the behaviour and
strength of cold form seel sections.
Rec. Stiffener
with Lip
Fig-1: Typical view of channel sections
2. OBJECTIVES OF RESEARCH WORK
There are different type of meshing that is adaptive,
proximity & curvature, curvature , proximity, uniform in
which types adaptive type meshing are used for modelling
analysis. In meshing relevance are three types coarse,
medium and fine. The analysis of modelling fine type of
relevance is used. No. of node system are applying on
section.
The objectives of this research work are to study:

To carry out design and analysis of Cold form steel
(channel section with and without stiffener, V
stiffener and Rectangular stiffener) using IS 801 1975 manually.

To analyse same sections using FEM based ANSYS
software and determine the load carrying capacity
and deflection for both with and without stiffeners.
To optimize size of the web stiffener by considering
different combinations of stiffener viz. V- stiffeners,
Lips, and Rectangular stiffeners and validate using
same length specimen taken for analytical work.
To investigate behavior of a frame with cold form
steel section and optimized cold form steel section
with different stiffeners.


Fig-2: CFS section model
3. ANALYTICAL STUDY
The Channel Section of 100 X 40 X 2 mm is considered
for the analytical purpose based on combinations. The lip for
channel section is considered from 10mm to 30mm.
Similarly different V stiffener and rectangular stiffener is
considered. The section is calculated and judged on its
behaviour under loading condition. The specimen is tested
for the one point loading. Total length of specimen is 1000
mm. The supports are kept at the distance of 50mm from
both the ends of the beam. The load is applied at the at the
midspan. Numerical analysis is carried out for channel
sections by ANSYS-version 18.1 software.
Fig-3: Meshing of channel section in ANSYS
3.1 Material Properties
The material properties of Cold form steel are as follows.
Table-1 Material properties
Yield Strength
235 N/mm2
Modulus of Elasticity
2x105 N/mm2
Poisson ratio
0.3
Modulus of Rigidity
0.769x105 N/mm2
The yield stress
250Mpa
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Fig-4: Deformation of channel section with rectangular
stiffener
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e-ISSN: 2395-0056
Volume: 06 Issue: 07 | July 2019
p-ISSN: 2395-0072
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Chart-2: Strain
Fig-5: Deformation of C section providing with lips
3.3 Analytical results
For the analysis of results 6 different sections are used with
or without stiffener and lip. In analysis we obtained
deformation, stress and strain is given below.
Table-1: Deformations of Channel section with and
without stiffeners
Details
Deformatio
n (mm)
Strain
C Section Without
Lip
3.01
0.0034
85.227
C Section With Lip
1.89
0.00344
63.559
C Section With V
Stiffener Without
Lip
2.6
0.00289
85.970
C Section With V
Stiffener With Lip
3.6
0.00400
63.971
C Section With
Rectangular
Stiffener Without
Lip
2.48
0.00276
78.125
C Section With
Rectangular
Stiffener With Lip
2.3
0.00256
70.754
Chart-3: Stress
Stress
(N/mm2
)
From analytical results observed optimum load carrying
capacity, deformation, strain, stress of with and without
stiffener and lip for channel section. Maximum deformation
and strain for C section with v stiffener with lips 3.6 mm,
0.00400 respectively. Maximum stress for C section with v
stiffener without lips 85.970 N/mm2.
4. EXPERIMENTAL STUDY
The size of channel Section 100 X 40 X 2 mm is
considered for the experimental purpose. The optimize size
of lip for channel section is considered from 30mm The
section is calculated and judged on its behaviour under
loading condition. The specimen is tested for the one point
loading. The length of beam considered for experimental as
well as analytical is 1000mm. When the support will rest at
50mm from both sides support to support clear distance is
900mm. loading is done at l/2 distance one line loading
which will generate the point load condition. The supports
are kept at the distance of 50mm from both the ends of the
beam. The load is applied at the midspan. The supports kept
at certain overhang to avoid slip of specimen during the
experimental work.
Chart-1: Deformation
Fig-6: Experimental test setup
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Volume: 06 Issue: 07 | July 2019
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Fig-7: Test specimens
Chart-4: Deformation
The graph shows maximum deformation for rectangular
stiffener with 30mm lip section is 3.06mm at maximum load
42.25 KN.
5. ANALYTICAL
COMPARISION
AND
EXPERIMENTAL
RESULTS
Comparison of experimental and analytical
displacement for various channel section was plotted in Fig.
The von mises stress and strain for the various profiles were
noted at the time of failure load.
Fig-8: Channel section with stiffener failure pattern
Table-3: Comaparision of channel section
Experimental
Analytical
Deformatio
Deformatio
Load
ns
ns
(KN)
(mm)
(mm)
Details
Load
(KN)
C Section
Without Lip
25
2.95
3.01
4.1 Experimental results
C Section With
Lip
30
3.02
1.89
The experimental testing is carried out on universal testing
machine for different sections. This results shows the
behaviour of CFS section after deformation.
C Section With
30
2.56
2.6
Fig-9: Deformation of channel
V Stiffener
Without Lip
Table-2: Deformation of sections under different load
Details
Load (KN)
Deformations
(mm)
C Section Without Lip
25
2.95
C Section With Lip
30
3.02
C Section With V Stiffener
Without Lip
30
2.56
C Section With V Stiffener
With Lip
34.5
2.89
C Section With Rectangular
Stiffener Without Lip
36.5
2.952
C Section With Rectangular
Stiffener With Lip
42.25
3.06
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C Section With
34.5
2.89
3.6
C Section With
Rec. Stiffener
Without Lip
36.5
2.952
2.48
C Section With
Rec. Stiffener
With Lip
42.25
3.06
2.3
V Stiffener With
Lip
|
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Volume: 06 Issue: 07 | July 2019
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
Stress strain curves and load deflection curves for
all channel section are linear.

The comparative study reveal that rectangular
channel section have high load carrying capacity
and maximum local buckling as compare to other
section.
REFERENCES
S. Senthil Selven and Wasim Reza “Experimental Study
on Flexural Behaviour of Cold Formed Steel Channel and
I Sections Providing Angle Stiffener on the Web” Indian
Journal
of
Science
and
Technology,
Vol9(35),DOI:10.17485/ijst/2016/v9i35/95967,
2016.
[2] Ibrahim Elkersh “Experimental investigation of bolted
cold formed steel frame apex connections under pure
moment” Ain Shams engineering journal locate
doi:10,2016/j.asej.2010.09.002.
[1]
Chart-5: Comparision of experimental and analytical
results
Comparison of Analytical & experimental study proved that
experimental rectangular channel section with 30 mm lip
carry 42.25 KN load, 3.06 mm deflection, strain 0.0034 and
stress 89.51 N/mm2 is more than analytical rectangular
channel section with 30mm lip.
6. CONCLUSIONS
[3]
Cheng Yu and Benjamin W. Schafer “Distortional
Buckling Tests on Cold-Formed Steel Beams” Journal of
Structural Engineering, Vol.132, Pg.No. 515-528, 2006.
[4]
Jothilakshmi. M, Dinesh. A, Balaji. C, “Analytical study on
the behaviour of cold formed steel double channel beam
sections” ISSN 0973-4562 Vol. 10 No.85, 2015.
Govindasamy.P, sreevidya.V, Dr. L.S Jayagopal
“Comparative study on Cold formed purlins for
Distortional Buckling behaviour” International journal
of Engineering science and Research technology, doi: 5
May 2013 ISSN:2277-9655.
Marsel Garifullin, Udo Nackenhorst “Computational
analysis of Cold formed Steel Columns with initial
imperfections”www.ScienceDirect.com/International
scientific Conference Urban Civil Engineering and
municipal
facilities,
SpbUCEMF-2015
doi:10.2016/j.proeng.2015.08.239.
IS:801-1975 “Code practice for use of cold formed light
gauge steel structural members in general building
construction ”Bureau of Indian Standards, UDC
624.014.2:693.814:69.001.3
Sp 6 (5)-1980 Cold formed light gauge steel structures
hand book.
The following conclusions can be made based upon the
experimental results:
The parametric study was performed using finite element
ANSYS analysis. The following detailed observations and
conclusions can be made.

The ANSYS results were generally in good
agreement with the test results.

It was observed that of the parameters varied in the
test spacing between the analysis results and
experimental results. As the load was increased the
amount of deformation, stress and also strain
increased.

The load capacity of Sections was observed to
decrease with the increase of width of beam,
because local buckling occurred earlier.
[5]
[6]
[7]
The following conclusions can be made based upon the
experimental results.

Without stiffener with 30 mm lip channel section
carry more loads is 30KN and its deformation is
3.02mm when compared to without stiffener with &
lip

V stiffener with 30 mm lip channel section carry
more load 34.5 KN and its deformation is 2.89 mm
as compared to V stiffener without lip

Rectangular stiffener with 30 mm lip channel
section carry more load 42.25 KN and its
deformation is 3.06 mm as compared to rectangular
stiffener without lip
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